Preoperative evaluation value of aortic arch lesions by multidetector computed tomography angiography in type A aortic dissection

Prognostic impact of branch vessel involvement on organ malperfusion and mid-term survival in patients with acute type A aortic dissection

BACKGROUND

This study aimed to investigate the impact of branch vessel involvement on organ malperfusion and mid-term survival in patients with acute type A aortic dissection (ATAAD).

METHODS

Between January 2019 and December 2020, 493 consecutive patients with angiographically confirmed ATAAD were retrospectively analysed. Preoperative computed tomography angiography parameters (branch artery involvement, longitudinal extent of dissection) were reviewed. The incidence of organ malperfusion, in-hospital mortality, and mid-term outcomes of patients with and without branch vessel involvement were compared.

RESULTS

Branch vessel involvement was detected in 407 patients (82.6%), and organ malperfusion was observed in 234 patients (47.5%). The incidence of organ malperfusion was significantly higher in patients with branch vessel involvement compared with patients without it (52.6% vs. 23.3%, p < 0.001). Patients with coronary artery involvement (32.5%) were more likely to manifest as clinical malperfusion, whereas it occurred only 19.4% in patients with renal artery involvement. In-hospital mortality was higher in patients with branch vessel involvement (19.9% vs. 8.1%, p = 0.010). Median follow-up time was 16.1 months. Two-year survival rate was lower in patients with branch vessel involvement (76.3% vs. 84.5%, p = 0.085) or organ malperfusion (68.3% vs. 86.0%, p < 0.001). Multivariable analysis identified cardiac, cerebral, visceral and renal malperfusion as independent predictors for in-hospital mortality.

CONCLUSIONS

Only a small proportion of branch vessel involvement was associated with corresponding organ malperfusion in patients with ATAAD. Branch vessel involvement had a greater effect on short-term outcomes than mid-term survival, and organ malperfusion was related to a worse prognosis beyond it.

Importance of Anatomical Variation of the Hepatic Artery for Complicated Liver and Pancreatic Surgeries: A Review Emphasizing Origin and Branching

Knowledge of anatomical variations of the hepatic artery from its origin to intrahepatic segmentation is of utmost importance for planning upper abdominal surgeries including liver transplantation, pancreatoduodenectomy, and biliary reconstruction. The origin and branching pattern of the hepatic artery was thoroughly described by the classification of Michels and Hiatt. Some rare variations of the hepatic artery were classified by Kobayashi and Koops. By the use of the multidetector computed tomography (MDCT) technique, the branching pattern of the hepatic artery can be visualized quite accurately. Unawareness of these arterial variations may lead to intraoperative injuries such as necrosis, abscess, and failure of the liver and pancreas. The origin and course of the aberrant hepatic arteries are crucial in the surgical planning of carcinoma of the head of the pancreas and hepatobiliary surgeries. In liver transplant surgeries, to minimize intraoperative bleeding complications and postoperative thrombosis, exact anatomy of the branching of the hepatic artery, its variations and intrahepatic course is of utmost importance. This review discusses variations in the anatomy of the hepatic artery from its origin to branching by the use of advanced imaging techniques and its effect on the liver, pancreatic, biliary and gastric surgeries.

The left-sided aortic arch variants: prevalence meta-analysis of imaging studies

PURPOSE

To estimate the prevalence of the left-sided aortic arch (LSAA) variants, and the effect of possible moderators on variants' detection.

METHODS

A systematic online literature search was conducted. The pooled prevalence with 95% confidence intervals was estimated for the typical and atypical branching patterns to compare the overall proportions of different variants. Meta-regression analyses were performed to investigate the effect of the subjects' gender and geographical region, and the multidetector computed tomography (MDCT) scanner's technology on the estimated prevalence.

RESULTS

In total, 18,075 cases from 23 imaging studies were included and 33 different LSAA variants were detected. The estimated heterogeneity was statistically significant. Based on the estimated prevalence, approximately 77% of the population is expected to have the typical branching anatomy with sequence brachiocephalic trunk-left common carotid artery-left subclavian artery, and 23% variant branching patterns. Approximately 71%, 23%, 2%, and 0.1% of the atypical populations are expected to have two, four, three, and five emerging branches, respectively. The meta-regression analyses showed that the number of detector rows of the MDCT scanner, and the subjects' geographical region are statistically significant moderators of the estimated prevalence.

CONCLUSION

The current findings indicate that the prevalence of the LSAA variant branching anatomy is significantly affected by the subjects' geographical region and the MDCT scanner's technological improvement, with the advanced scanners to facilitate the detection of the aortic arch variants. However, due to the heterogeneity among studies, further research is required.

The Role of Dual-Source Computed Tomography Angiography in Evaluating the Aortic Arch Vessels in Acute Type A Aortic Dissection: A Retrospective Study of 42 Patients

Background

This study aimed to investigate the role of dual-source computed tomography angiography (DSCTA) to evaluate the anatomy of the aortic arch vessels in patients with acute Type A aortic dissection (AD).

Material/Methods

A retrospective clinical study included 42 patients with acute Type A AD who underwent DSCTA and were treated in our hospital between January 2018 and December 2018. The findings were compared with a control group of 45 healthy individuals with hypertension and without aortic arch lesions.

Results

The diagnostic accuracy of DSCTA in patients with acute Type A AD was almost 100%. The innominate artery was most frequently affected. The mean DSCTA imaging measurements for the root of the innominate artery, the left common carotid artery, and the left subclavian artery, in the coronal plane of the aortic arch, were 17.7±3.7 mm, 17.7±3.7 mm, and 12.9±3.1 mm, respectively. The angles formed by the origin of the three aortic arch branches vessels and the aortic arch were 70.5±10.2°, 58.5±15.5°, and 90.2±22.7°, respectively. In the transverse plane of the aortic arch, the mean angles were 110.5±22.3°, 100.3±15.2°, and 95.4±10.6°, respectively. These DSCTA imaging findings were significantly different in the patient group compared with the control group.

Conclusions

DCTA demonstrated that patients with Type A AD showed anatomic differences in the aortic arch vessels. These findings may help surgeons to develop treatment strategies and select the most appropriate vascular grafts and stents.